The present invention pertains generally to hoist trucks, and more particularly to an improved hoist assembly mountable on a conventional pickup truck in such manner as to avoid interference with the cargo-carrying capacity thereof.
A hoist or gin pole truck is a very specialized vehicle whose use is usually limited to the lifting and transporting of heavy objects for short distances. In all but the most active operations, such hoist trucks are idle a majority of the time, therefore yielding an undesirably low return on capital investment. Thus, it would be desirable to provide a vehicle having the capabilities of a conventional hoist or gin pole truck yet with the added utility of a cargo carrier as, for example, a conventional pickup truck. No known prior art vehicle achieves such a dual function in a satisfactory and economical manner.
The following patents are representative of the prior art: Sears, U.S. Pat. No. 3,115,256; Proctor, U.S. Pat. No. 2,843,360; Garnett et al., U.S. Pat. No. 2,715,014; Miller et al., U.S. Pat. No. 3,111,225; Burkland, U.S. Pat. No. 3,980,276; Powers, U.S. Pat. No. 2,746,717; Troche et al., U.S. Pat. No. 2,611,580.
Of the above-cited references, only Burkland describes a hoist device for installation on an ordinary pickup truck. The Burkland device, however, is employed at the front of the truck by attachment to a specially adapted front bumper, thus requiring removal of the device prior to resuming ordinary transport operations with the truck. Furthermore, the Burkland hoist device can only be used while the vehicle is stationary, thus being clearly incapable of towing and similar operations.
The remaining cited refernces describe special purpose vehicles with hoist equipment or the like that substantially interferes with the vehicles cargo-carrying capacity, some to a much greater extent than others. Each such vehicle has interfering equipment either above the entire length of the potential storage area, or within the sidewalls thereof, or both. The vehicle described by Sears provides a hoist device which, by comparison to the others, interferes least with the cargo area; yet, because it does not show side panels and a tail gate characteristic of a conventional pickup truck, its versitility as a cargo-carrying vehicle is limited.